1. Field of the Invention
The invention relates to surgical procedures and, more particularly, to techniques for installing an implantable device that can be used as a fluoroscopic marker or as a fluoroscopic marker/tissue connector.
2. Description of the Prior Art
While the present invention has application in various types of surgical procedures, it will be described in the context of gastric bypass surgery as used for the treatment of obesity. The most common gastric bypass procedure performed today is known as the Roux-en-Y gastric bypass procedure (RYGB). In the RYGB procedure, a six-inch to eight-inch incision is made that extends from the end of the sternum to just above the navel. More recently, the RYGB has been performed laparoscopically in order to minimize trauma, healing time and risk of infection. The stomach is completely divided into two unequal portions—a small upper pouch and a large lower gastric pouch (excluded stomach). The upper pouch typically measures less than about one ounce, preferably about one-half ounce, or 15 cc, while the excluded stomach remains generally intact and continues to secrete stomach juices that flow through the intestinal tract.
The small intestine is severed at a location distal of the duodenum or proximal of the jejunum. The severed end of the small intestine then is brought from the lower abdomen, behind the colon and the bypassed stomach, and joined with the upper pouch to form an end-to-end anastomosis created through a half-inch opening, also called the stoma. This rerouted segment of the small intestine is called the “Roux loop” and carries food from the upper pouch to the remainder of the intestines where the food is digested. The severed end of the segment of the duodenum that is part of the excluded stomach is connected to the Roux loop by means of an anastomotic connection. The connection is located approximately 100 cm from the stoma, and typically is made by using a stapling instrument. Prior to completion of the surgical procedure, a gastropexy commonly is performed to attach the excluded stomach to the abdominal wall or to the diaphragm, primarily to prevent the excluded stomach from being displaced within the abdominal cavity.
The RYGB procedure described permits digestive juices from the bypassed stomach, pancreas and liver to join the food stream from the small upper pouch and Roux loop to begin digesting the food. The remainder of the intestinal tract is not disturbed. Due to the small size of the upper pouch, patients are forced to eat at a slower rate and are satiated much more quickly, thereby reducing their caloric intake. Moreover, because the food enters the intestines directly, certain undesirable foods such as sweets create unpleasant feelings of nausea, diarrhea, nervousness, and sweating, which in turn discourages patients from developing or maintaining unhealthy eating habits. The RYGB procedure typically demonstrates a loss of at least 50% of excess body weight; approximately 60% of the patients will be able to maintain this weight loss for at least five years.
In certain cases it is necessary to perform post-operative surgical procedures. For example, some patients require that the excluded stomach be decompressed post-operatively. In order to accommodate this possibility, it has been known to insert a gastrostomy tube through the abdominal wall and into the excluded stomach and leave it there for several days until the need for decompression passes. In such cases, the gastrostomy tube has been provided with a silastic ring having a metal marker. The metal marker permits the excluded stomach to be quickly and accurately located in the abdominal cavity by fluoroscopic examination. While the practice of inserting a gastrostomy tube is effective to avoid the need for post-operative decompression, it also is an unnecessary procedure for many patients. Experience with patients that have not been fitted with a gastrostomy tube at the time of surgery shows that decompression is needed only in about one out of every 50-75 patients.
A problem in performing decompression in patients that have not had a gastrostomy tube inserted at the time of surgery is that the large pouch cannot be located accurately and, once located, cannot be held in a stable position for purposes of inserting an endoscope or trochar/cannula. In order to deal with such problems, it has been known to perform the gastropexy by using a circular wire suture having a diameter of approximately one inch. Because the suture is made of metal, it serves as a marker for fluoroscopic location of the bypassed stomach. The suture also assists in stabilizing the excluded stomach for post-operative insertion of an endoscope or a trochar/cannula.
The use of markers to subsequently locate areas of surgical interest is well known, particularly in the field of breast biopsies. See, for example, U.S. Pat. Nos. 4,592,356; 5,059,197; 5,158,084; 5,197,482; 5,221,269; 5,409,004; 5,709,697; 5,989,265; 6,356,782 and 6,405,733. In general, these patents disclose the concept of using metallic tissue markers that are implanted or otherwise attached to an internal portion of a patient's body. FIGS. 2B and 2C of the '782 patent disclose ring-like markers, while the '269 patent discloses a helical wire marker. Many of the patents in question disclose barbs of various types to retain the marker in place.
A problem with prior markers is that they have been difficult to use and install. In particular, such markers have not facilitated the attachment of the marker to the portion of the body to be marked. Moreover, such markers have not facilitated the attachment of one portion of the body to another. Although the use of hooks or barbs makes the implantation of a marker easier to perform, such hooks or barbs are generally undesirable for purposes of long-term retention of the marker. The use of a wire suture, while effective as a marker and connector, generally is undesirable because it can be difficult to install. Moreover, a wire suture also may not provide an effective technique to hold tissue in place for purposes of inserting objects such as an endoscope or a trochar.
Desirably, a surgical marker/connector would be available that would be easy to use and install, and which would permit portions of the body that need to be connected to each other to be connected in a convenient and secure manner. Preferably the marker/connector would be made of a material that would facilitate location by fluoroscopic techniques. In the particular case of a gastropexy performed as part of the RYGB procedure, the marker/connector preferably would permit an endoscope or a trochar/cannula to be inserted quickly and accurately.